I think the fundamental problem with newsletter / blog subscription model is that it is just way too expensive for the subscriber. There is a rule of thumb that

I think the fundamental problem with newsletter / blog subscription model is that it is just way too expensive for the subscriber. There is a rule of thumb that people are usually prepared to pay about $2 for an hour of entertainment: cost of books, magazines, renting a movie from online streaming service, even netflix/hbo subscription based on the actual usage hours fall in a roughly the same price bracket. But paying $5 or $10 for one blog subscription seems very expensive when ou realise how much actual time you spend reading it. Not viable in the long term.